Intercondylar distances of the human temporomandibular joints

In a sample which included subjects of the Croatian population we made measurements of intercondylar distances between the temporomandibular joints in radiographs. A total of 101 subjects of both sexes ranging in age from 20 to 80 years, mostly residents in Zagreb, were evaluated. We measured the intercondylar distances from the condyle centers in the postero-anterior cranial radiographs which had previously been examined and traced on acetate paper. The measuring points were digitized prior to measurements. A special system of coordinates was devised for each radiograph. The results of our measurements were assessed by ANOVA analysis. The intercondylar distance between the two temporomandibular joints was within the range of 110 and 145 mm, with the mean of 126 mm. In men the intercondylar distance was within the range of 116 and 145 mm, with the mean of 130.2 mm. In women the distance ranged from 110 to 138 mm, with the mean of 123.5 mm. There was a significant difference between the two sexes. From a review of the literature, it is apparent that the results of our measurements do not support the results of similar studies assessed by a number of researchers in other countries. The intercondylar distance in the Croatian sample was 5.25% larger than the maximal values of the same parameters in other populations suggesting larger craniofacial skeletons. The development of this radiographic assessment method should improve evaluation of subjects seeking treatment.     

Morphometric analysis of Cartesian coordinates of the human skull

A method for locating the three dimensional coordinates of cranial landmarks with respect to the Frankfort, midsagittal, and coronal planes is presented. Sliding calipers were used to obtain the distances from left and right porion and apex to each landmark, except for a few points where spreading calipers are required. In the present example, 35 landmarks (for a total of 105 measurements) were located for each of 35 Peruvian precolumbian skulls. These distances were entered into a program (SKULL) which calculates the Cartesian coordinates of each landmark. The XYZ coordinates of each landmark contain all the information necessary for calculation of the distances between any two landmarks, and these distances may also be obtained as output from program SKULL, if desired (595 distances if all 35 landmarks are used). Reliability of the location of coordinates was determined by comparing computed distances among selected landmarks from program SKULL with traditional anthropometric measurements. Satisfactory agreements were found. Direct multivariate analysis of the coordinates of the landmarks produced insights not available in traditional multivariate analysis of conventional anthropometric measurements.     

Curvilinear-tree-ring measurements in archaeological wood samples from X-ray computed tomography

In this paper X-ray computed tomography imaging data is used to perform nondestructive tree-ring width measurements in three archaeological wooden samples. Measurements of the curvilinear-tree-ring widths are performed using two approaches: firstly, measuring manually the distance between two points on two consecutive tree-rings along two orthogonal radii and, secondly, using a recently proposed computational approach which averages all calculated pairwise radial distances between two consecutive tree-rings along the whole tree-ring profile. The results show that the irregularity of the tree-ring shape is an important factor to be considered in performing curvilinear-tree-ring measurements. For irregular shaped tree-rings, deviations up to 1.15 mm were observed between the output of both measurement’s approaches. It is concluded that tree-ring width measurements along only two orthogonal radial rays are not always accurate enough and therefore averaging along the whole tree-ring profile is recommended.     

Biological affinities between the migrant groups of fishermen of Puri Coast, Orissa, India

Biological affinities between the three endogamous groups of marine fishermen of Puri are examined with the help of nine anthropometric measurements and 22 dermatoglyphic traits of fingers and palms. The results are interpreted in the light of their ethnic, geographical, and migrational backgrounds. Multiple discriminant analysis and Mahalanobis's generalized distances suggest higher discrimination of populations with reference to anthropometric traits as compared to that in dermatoglyphic variables. While the nature of interpopulation distances conforms to the geographic pattern in anthropometrics, no clear picture emerges in the dermatoglyphic distances supporting either ethnic or geographic evidence.     

Genes that affect morphogenesis of the murine mandible. Recombinant-inbred strain analysis

The CXB set of recombinant inbred mouse strains provided an opportunity to observe the effects of reassorted subsets of genes on the shape of the mandible. The distances between 12 landmarks in all paired combinations were calculated to evaluate genetic control in small regions. The genetic relationships between interlandmark distances revealed genes to have most of their effects in localized regions, and the greater heritabilities usually to apply to those distances between adjacent landmarks. Interrelationships between measurements are usually explicable on a developmental basis. It is proposed that genes of this sort bring about the changes seen in organ shape during evolution. A model plan for the organization of gene activation during morphogenesis is described.     

Mining biochemical information: lessons taught by the ribosome

The publication of the crystal structures of the ribosome offers an opportunity to retrospectively evaluate the information content of hundreds of qualitative biochemical and biophysical studies of these structures. We assessed the correspondence between more than 2,500 experimental proximity measurements and the distances observed in the ribosomal crystals. Although detailed experimental procedures and protocols are unique in almost each analyzed paper, the data can be grouped into subsets with similar patterns and analyzed in an integrative fashion. We found that, for crosslinking, footprinting, and cleavage data, the corresponding distances observed in crystal structures generally did not exceed the maximum values expected (from the estimated length of the agent and maximal anticipated deviations from the conformations found in crystals). However, the distribution of distances had heavier tails than those typically assumed when building three-dimensional models, and the fraction of incompatible distances was greater than expected. Some of these incompatibilities can be attributed to the experimental methods used. In addition, the accuracy of these procedures appears to be sensitive to the different reactivities, flexibilities, and interactions among the components. These findings demonstrate the necessity of a very careful analysis of data used for structural modeling and consideration of all possible parameters that could potentially influence the quality of measurements. We conclude that experimental proximity measurements can provide useful distance information for structural modeling, but with a broad distribution of inferred distance ranges. We also conclude that development of automated modeling approaches would benefit from better annotations of experimental data for detection and interpretation of their significance.     

Continuous tooth eruption in Australian aboriginal skulls

Increases in the distance from the cemento-enamel junction to the alveolar crest (CEJ-AC) have often been attributed to senile atrophy of the bone or to the effects of periodontitis, without reference to the condition of the alveolar crest. This study investigated the relationship between CEJ-AC distance, tooth wear, gender, site of the CEJ-AC measurements, and age in 161 pre-white-contact Australian aboriginal skulls. Individual teeth were included in the study when there was no evidence of dehiscence, periodontitis, or abscess cavity formation in the supporting alveolar bone. The CEJ-AC distances increased as the severity of attrition increased; in male skulls, CEJ-AC distances were greater than in female skulls for all categories of tooth wear. In general, CEJ-AC distances measured on the mesial aspects of teeth were greater than those recorded distally; lingual distances generally exceeded buccal recordings. The best explanation of these findings and similar reports in the anthropological literature is that continuous tooth eruption occurred without the concomitant coronal movement of alveolar bone. This conclusion has significant ramifications for anthropological, epidemiological, and clinical studies which use the CEJ and AC as reference points when measuring periodontal attachment loss (periodontitis).     

The quantitation of nuclear Overhauser effect methods for total conformational analysis of peptides in solution. Application to gramicidin S.

The [1H:1H] nuclear Overhauser effects (NOE's) and spin-lattice relaxation times (T1's) are reported for the backbone protons of the decapeptide gramicidin S. Several methods for calculating interproton distances from these measurements are presented. Ratios of interproton distances were obtained from [1H:1H] NOE's and from the combination of [1H:1H]NOE'S and T1 values. Actual proton-proton distances were calculated from these ratios either by using the known distance between two geminal protons or distances derived from scalar coupling constants. The interproton distances calculated for gramicidin S are consistent with a II' beta-turn/antiparallel beta-sheet conformation.     

Using interpubic distance for sexing manakins in the field

ABSTRACT Field methods for determining the sex of birds are often limited due to morphometric overlap between sexes, intermediate plumages, seasonality, and reliance on subjective age classification. Interpubic distance, characterized in birds as the distance between the distal ends of the pubic bones, has not been formally tested as a method for determining the sex of birds, despite references among parrot breeders and the frequent use of analogous measurements in mammals. We developed a harmless and easily performed field method for measuring interpubic distance in studies involving bird capture, and compared the interpubic distances of known sex White‐ruffed Manakins (Corapipo altera), Orange‐collared Manakins (Manacus aurantiacus), and Blue‐crowned Manakins (Lepidothrix coronata) to evaluate the possible use of this measurement to determine sex. Using interpubic distance ranges based on 85% confidence intervals where overlap existed between sexes, the sex of 92.8–100% of all manakins in our study was accurately determined with no misclassification. Interpubic distance performed better than plumage‐based methods that sexed 74.0% of all individuals and misclassified 1.5%. Using linear discriminant analysis, we developed classification equations that allowed us to accurately determine the sex of all individuals with 100% accuracy using mass and interpubic distance. Additionally, we compared the interpubic distances of female White‐ruffed Manakins to evaluate the potential to determine age and reproductive status. Despite an apparent relationship between interpubic distance, age and reproductive status, we concluded that interpubic distance has limited use for determining age and reproductive status due to extensive overlap (31.6–100%), but shows potential in other applications. Based on these results, we endorse the use of interpubic distance to determine the sex of manakins. We encourage further study to develop additional classification equations using different morphometric measurements and to test the efficacy of interpubic distance to determine sex in other bird species.     

Anthropometric variation and the genetic structure of the Jirels of Nepal

Anthropometric measurements (head length, head breadth, bizygomatic diameter, minimum frontal diameter, head circumference, and stature) for 526 adult Jirels are utilized to establish the pattern of phenotypic relationships between seven villages in eastern Nepal. An analytical framework is provided that justifies the interpretation of biological distances as minimum genetic distances. Using this approach, estimates of the minimum pairwise genetic distances between villages and the minimum FST for the population are derived from the purely phenotypic data. The FST obtained in this way is consistent with results obtained from other data available for this population, confirming the utility of phenetic analysis of quantitative traits for elucidating genetic structure.